Toilet system

ABSTRACT

A toilet system comprising: a cistern for containing flush water; a toilet having a bowl, the bowl having one or more apertures which are in fluid communication with a water intake aperture of the toilet and through which flush water flows when the toilet is flushed; a conduit for transporting flush water from the cistern to the water intake aperture; and a gas removal device positioned around the conduit and defining an inner aperture through which the conduit passes, there being a peripheral space between the exterior of the conduit and an inner surface of the inner aperture, and the gas removal device being operable to suck gas into the device through the inner surface of the inner aperture.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the national stage of International Application No.PCT/GB03/004720 and claims benefit in accordance with 35 U.S.C. §119 ofthe priority of United Kingdom Patent Application No. GB 0225750.9,filed Nov. 5, 2002.

THIS INVENTION relates to a toilet system, and in particular concerns atoilet system comprising a gas removal device for removing gastherefrom. The present invention also provides a gas removal devicewhich may be used with a wide variety of toilet systems.

It has been proposed in the past to provide a bathroom ventilationappliance that removes malodorous gas directly from the bowl of atoilet, by the extraction of air through the water jackets locatedaround the rim of a toilet bowl. An example of such a system isdisclosed in U.S. Pat. No. 5,386,594 (Hilton). In this document, amanifold is provided as an extension to a conduit that connects a watertank of a toilet system and the upper surface of the toilet itself.Hence, water passing from the water tank to the toilet passes throughthe manifold, and gas is sucked into the ventilation appliance throughan inner surface of the manifold.

This approach suffers from several drawbacks. Firstly, the fact that themanifold acts as an extension to the conduit connecting the water tankand the toilet means that, in installing the ventilation appliance in atoilet system, the water tank must be raised through an additionalheight to accommodate the manifold.

Additionally, the manifold must be provided with connectors to connectthe manifold to the conduit and to the upper surface of the toilet in anairtight fashion, and clearly this means that a different type ofconnector is required for each different type of conduit and/or toilet.

Further, the device disclosed in U.S. Pat. No. 5,386,594 comprises acomplex and awkward “P-trap” for preventing the return of malodours airto the atmosphere following the deactivation of the gas removalmechanism. This P-trap mechanism requires a proportion of the watersupplied to the toilet by the water tank at each flush to be divertedthereto, and due to the complexity of this system the P-trap mechanismis prone to failure.

It is an object of the present invention to seek to alleviate some orall of the above difficulties.

Accordingly, one aspect of the present invention provides a toiletsystem comprising: a cistern for containing flush water; a toilet havinga bowl, the bowl having one or more apertures which are in fluidcommunication with a water intake aperture of the toilet and throughwhich flush water flows when the toilet is flushed; a conduit fortransporting flush water from the cistern to the water intake aperture;and a gas removal device positioned around the conduit and defining aninner aperture through which the conduit passes, there being aperipheral space between the exterior of the conduit and an innersurface of the inner aperture, and the gas removal device being operableto suck gas into the device through the inner surface of the inneraperture.

Advantageously, the gas removal device comprises an interface portionwhich is positioned around the conduit, the interface portion beingprovided with a pair of seals to seal the interface portion to thetoilet and to the water tank.

Preferably, the gas removal device comprises a liquid detectionmechanism to detect the flow of liquid through the conduit and cease thesucking of gas into the device upon such detection.

Conveniently, the liquid detection mechanism comprises a pair ofelectrically conductive contacts, having a gap defined therebetween,mounted on an arm such that the contacts are in a flow path of liquidcarried by the conduit, an electrical connection between the contactsbeing made by the presence of water in the gap between the contacts.

Advantageously, following the ceasing of sucking of gas into the gasremoval device due to the detection of a flow of liquid through theconduit, the sucking of gas into the gas removal device is resumed onceno more liquid is detected flowing through the conduit.

Preferably, the system further comprises a use detection mechanism todetect use of the toilet and activate the gas removal device in responseto such detection.

Conveniently, the use detection mechanism comprises a pressure sensoroperable to detect the weight of a person using the toilet.

Advantageously, the use detection mechanism comprises a wirelessconnection to the gas removal device.

Preferably, the system further comprises a timer mechanism operable todeactivate the gas removal device after a predetermined time has elapsedfollowing a time when the detection mechanism detects that use of thetoilet has ceased.

Conveniently, the system further comprises a conduit for guiding gasremoved by the gas removal device and feeding the removed gas into asoil stack of the toilet system.

Advantageously, the system further comprises a one-way valve whichallows the removed gas to be fed into the soil stack from the conduitbut prevents gas from entering the conduit from the soil stack.

Preferably, the one-way valve comprises a flexible diaphragm whichblocks an aperture in the valve when gas attempts to flow from the soilstack to the conduit but distorts to allow gas to flow from the conduitto the soil stack.

Conveniently, an internal diameter of the inner aperture is at least 6.3cm.

Advantageously, the gas removal device comprises one or more batteriesto provide power to the gas removal device.

Preferably, the one or more batteries are rechargeable.

Conveniently, the system further comprises one or more turbines adaptedto be located in an area of the toilet experiencing, in use, a fluidflow, the flow of fluid past the one or more turbines producing power;and a connector to supply power so produced to the gas removal device ora battery thereof.

Advantageously, the gas removal device comprises a body that is adaptedto fit closely to a portion of the toilet, a part of the body havingvariable length.

Preferably, the part of the body having a variable length comprises ahollow, corrugated, flexible portion.

Another aspect of the present invention provides a toilet systemcomprising: a toilet having a bowl, the bowl having one or moreapertures which are in fluid communication with a water intake apertureof the toilet and through which flush water flows when the toilet isflushed; a cistern for containing flush water, the cistern having anoutlet through which flush water is ejected when the toilet is flushed,the cistern and the toilet being arranged such that, when flush water isejected from the cistern through the outlet thereof, a flow of flushwater follows a flow path and is received through the water intakeaperture of the toilet; and a gas removal device having an inneraperture, the gas removal device being positioned around the flow pathsuch that the flow path passes through the inner aperture and, whenwater flows along the flow path, an air gap exists between an innersurface of the inner aperture and an exterior of the flow.

Conveniently, the diameter of the inner aperture is at least 6.3 cm.

A further aspect of the present invention provides a gas removal devicefor use with a toilet system comprising a toilet having a bowl, the bowlhaving one or more apertures which are in fluid communication with awater intake aperture of the toilet and through which flush water flowswhen the toilet is flushed and a cistern for containing flush water, thecistern having an outlet through which flush water is ejected when thetoilet is flushed, the cistern and the toilet being arranged such that,when flush water is ejected from the cistern through the outlet thereof,a flow of flush water follows a flow path and is received through thewater intake aperture of the toilet, the gas removal device: defining aninner aperture; being adapted to be positioned around the flow path suchthat the flow path passes through the inner aperture and, when flushwater flows through the flow path, an air gap exists between an innersurface of the inner aperture and an exterior of the flow; and beingoperable to suck gas into the device through an inner surface of theinner aperture.

Advantageously, an internal diameter of the inner aperture is at least6.3 cm.

Another aspect of the present invention provides a gas removal devicefor removing gas from the bowl of a toilet, wherein: the devicecomprises an interface portion defining an aperture through which a flowpath of flush water may pass; the device is operable to suck gas intothe device through an inner surface of the interface portion; and thedevice comprises a liquid detection mechanism to detect the flow ofliquid through the aperture and cease the sucking of gas into the deviceupon such detection.

Preferably, the liquid detection mechanism comprises a pair ofelectrically conductive contacts, having a gap defined therebetween,mounted on an arm, an electrical connection between the contacts beingmade by the presence of water in the gap between the contacts.

Conveniently, the device further comprises a use detection mechanism todetect use of the toilet and activate the gas removal device in responseto such detection.

Advantageously, the use detection mechanism comprises a pressure sensoroperable to detect the weight of a person using the toilet.

Preferably, the use detection mechanism comprises a wireless connectionto the gas removal device.

Advantageously, the device further comprises a timer mechanism operableto deactivate the gas removal device after a predetermined time haselapsed following a time when the detection mechanism detects that useof the toilet has ceased, or after a predetermined time has elapsedfollowing the initial activation of the gas removal device.

Conveniently, the device further comprises a conduit for guiding gasremoved by the gas removal device and adapted to feed the removed gasinto a soil stack of the toilet.

Advantageously, the device further comprises a one-way valve whichallows the removed gas to be fed into the soil stack from the conduitbut prevents gas from entering the conduit from the soil stack.

Preferably, the one-way valve comprises a flexible diaphragm whichblocks an aperture in the valve when gas attempts to flow from the soilstack to the conduit but distorts to allow gas to flow from the conduitto the soil stack.

Conveniently, an internal diameter of the aperture is at least 6.3 cm.

Advantageously, the gas removal device comprises one or more batteriesto provide power to the gas removal device.

Preferably, the one or more batteries are rechargeable.

Conveniently, the device further comprises: one or more turbines adaptedto be located in an area of the toilet experiencing, in use, a fluidflow, the flow of fluid past the one or more turbines producing power;and a connector to supply power so produced to the gas removal device ora battery thereof.

Advantageously, the gas removal device comprises a body that is adaptedto fit closely to a portion of the toilet, a part of the body havingvariable length.

Preferably, the part of the body having a variable length comprises ahollow, corrugated, flexible portion.

A further aspect of the present invention provides a gas removal devicefor removing gas from the bowl of a toilet, the device comprising: oneor more turbines adapted to be located in an area of the toiletexperiencing, in use, a fluid flow, the flow of fluid past the one ormore turbines producing power; and a connector to supply power soproduced to the gas removal device or a battery thereof.

Another aspect of the present invention provides a method of adapting atoilet system, the toilet system initially comprising a toilet having abowl, the bowl having one or more apertures which are in fluidcommunication with a water intake aperture of the toilet and throughwhich flush water flows when the toilet is flushed and a cistern forcontaining flush water, the cistern having an outlet through which flushwater is ejected when the toilet is flushed, the cistern and the toiletbeing arranged such that, when flush water is ejected from the cisternthrough the outlet thereof, a flow of flush water follows a flow pathand is received in the water intake aperture of the toilet, the methodcomprising the steps of: providing a gas removal device, the gas removaldevice defining an inner aperture and being operable to suck gas intothe device through an inner surface of the inner aperture; andpositioning the gas removal device around the flow path such that, whenflush water flows along the flow path, an air gap exists between theinner surface of the inner aperture and an exterior of the flow.

In order that the present invention may be more readily understood,embodiments thereof will now be described by way of example, withreference to the accompanying drawings, in which:

FIG. 1 is a schematic view of the toilet system embodying the presentinvention; and

FIG. 2 shows a gas removal device embodying the present invention.

With reference firstly to FIG. 1, a toilet system 1 embodying thepresent invention comprises a water tank 2, which is adapted to hold aquantity of water 3 and which is provided with a substantially verticalconduit 4 extending downwardly therefrom. The water tank 2 is adapted toeject at least some of the water 3 held therein out of the water tank 2through the conduit 4 when a flush of the toilet system 1 is required.

The toilet system 1 further comprises a toilet 5. The toilet 5 comprisesa bowl 6, the bowl 6 having one or more apertures (not shown) on aninner surface thereof, preferably under a rim of the toilet bowl. Whenthe toilet 5 is flushed, water is ejected from the apertures on theinner surface of the bowl 6 as part of the flushing procedure.

The toilet 5 is provided with a water intake aperture 7 on an uppersurface thereof, and one or more channels are provided in the toilet toallow fluid communication between the apertures on the inner surfacethereof and the water intake aperture 7. These channels are commonlyreferred to as the water jackets of the toilet 5.

The water tank 2 and the toilet 5 are arranged so that water passingdownwardly through the conduit and ejected therefrom will be received inthe water intake aperture 7 of the toilet 5.

Hence, it will be understood that, during a flush of the toilet system1, water 3 is ejected downwardly from the water tank 2 through theconduit 4 and into the water intake aperture 7 of the toilet. The waterthen passes through the water jackets of the toilet and is ejected outof the apertures on the inner surface of the toilet bowl 6.

The toilet 5 is further provided with a soil stack 8, through whichwaste matter from the toilet is expelled.

The toilet system 1 described comprises conventional components.

The toilet system 1 further comprises a gas removal device 9. The gasremoval device 9 comprises a substantially ring-shaped interface portion10, which is flattened in shape and defines an inner aperture 11. Theinterface portion 10 is positioned between the water tank 2 and thetoilet 5, such that the conduit 4 passes through the inner aperture 11thereof, there being a peripheral space defined between the exterior ofthe conduit 4 and the inner surface of the inner aperture 11.

The interface portion 10 of the gas removal device 9 is provided with apair of ring-shaped seals or gaskets 12, which are respectively providedon upper and lower surfaces of the interface portion 10 and form a sealbetween the upper surface of the lower surface of the interface portion10 and the underside of the water tank 2, and between the lower surfaceof the interface portion 10 and the upper surface of the toilet 5.

The gas removal device 9 further comprises a conduit 13 which isconnected to the interface portion 10. A gas intake port is defined onan inner surface of the inner aperture 11 of the gas removal device 9.The gas intake port is in fluid communication with the conduit 13.

The conduit 13 is airtight and connects the gas intake port of theinterface portion 10 to a connector 14, which connects the conduit 13 tothe soil stack 8 and places the conduit 13 in fluid communicationtherewith, preferably in a selective manner, as will be described below.The conduit 13 is preferably flexible, so that it can be distorted toaccommodate different sizes of toilet or avoid anyinconveniently-located items or fittings in the bathroom.

The gas removal device 9 is operable to suck gas into the device 9through the gas intake port. To achieve this, a fan 15 is provided inthe conduit 13, the fan 15 being powered by a motor 16, although anyother suitable method of sucking in gas may be used as part of thepresent invention.

The toilet system 1 further comprises a use detection mechanism UD todetect use of the toilet 5 and to activate the gas removal device 9 inresponse to such detection.

The use detection mechanism UD may take any suitable form and may, forinstance, comprise a motion sensor operable to detect the presence of aperson in the region immediately above the seat of the toilet 5.Alternatively, the use detection mechanism UD may comprise a pressuresensor, which may be located in a suitable location to detect the weightof a person using the toilet 5.

As a further possibility, the use detection mechanism UD may comprise aswitch which is mounted on a wall in the vicinity of the toilet system1, or in another suitable location, so that a user of the toilet 5 canactivate the gas removal device 9 manually. In preferred embodiments ofthe invention, a switch is provided which may be located beneath theseat of the toilet 5, thereby acting as a pressure sensor to detect useof the toilet 5 automatically, or may alternatively be mounted on anearby wall and activated manually. It is envisaged that this will befound useful in situations where someone sitting on the toilet will notalways necessitate use of the gas removal device 9, for instance in ahousehold consisting mainly or entirely of women.

It is preferred, particularly in conjunction with this embodiment, thatthe use detection mechanism UD provided with a wireless connection R tothe gas removal device 9. This is partially for convenience, andpartially because users may often feel uneasy at the presence ofelectrical wires in a bathroom, as there may be a fear of receiving anelectric shock.

Use of the toilet system 1 will now be described. The use detectionmechanism detects the use of the toilet 5 and, as discussed above, thedetection may take one of several different forms. Upon the detected useof the toilet the fan 15 is activated, and rotates, thereby sucking airinto the gas removal device 9 through the air intake port. Hence, airwill be sucked directly from the toilet bowl, through the water jacketsof the toilet 5, into the inner aperture 11 of the gas removal device 9by flowing into the peripheral gap defined between the inner surface ofthe inner aperture 11 and the exterior of the conduit 4, and into thegas intake port. The removed gas passes through the conduit 13, past thefan 15, and is deposited into the soil stack 8 by the connector 14.

It will be appreciated that the provision of the peripheral gap betweenthe inner surface of the inner aperture 11 of the gas removal device 9and the exterior of the conduit 4 means that the gas removal device 9has little or no effect on the height of the water tank 2 with respectto the toilet 5. This is because the gas removal device 9 does notcomprise an extension of the conduit 4, as disclosed in U.S. Pat. No.5,386,594, but instead fits around the conduit 4.

In addition, the interface between the gas removal device 9 and theremaining components of the toilet system 1 is not critically dependentupon the diameter of the conduit 4. Indeed, if the inner aperture 11 ofthe gas removal device 9 is sufficiently large, the gas removal device 9may be used with any suitably configured toilet system 1.

It is understood that the widest commonly used conduits have diametersof around 5 cm (2 inches). In preferred embodiments of the invention,therefore, the inner diameter of the inner aperture 11 of the gasremoval device 9 is at least 6 cm (around 2 and one third inches) andmore preferably at least 6.3 cm (around 2 and a half inches).

In addition, installation of the gas removal device 9 in an existingtoilet system 1 is simple, since the gas removal device 9 is notactually fixed to the conduit 4. The interface portion 10 of the gasremoval device 9 is simply placed between the upper surface of thetoilet 5 and the lower surface of the water tank 2, and the water tank 2is then simply lowered on to the interface portion 10, with the gaskets12 forming appropriate seals between the upper surface of the toilet 5and the lower surface of the interface portion 10, and between the uppersurface of the interface portion 10 and the underside of the water tank2.

It will be appreciated that the above-described embodiment provides atoilet system 1 and gas removal device 9 therefor, which discreetlyremoves malodorous gases from the bowl 6 of the toilet 5, during use ofthe toilet 5, with the gas removal device 9 being easily and flexiblyintegrated into the toilet system 1 as a whole.

In preferred embodiments of the invention, the gas removal device 9further comprises a liquid detection mechanism 17 to detect the flow ofliquid through the conduit 4. In the illustrated embodiment, the liquiddetection mechanism 17 comprises a pair of electrically conductivecontacts 18 mounted near one another on an arm 19, such that thecontacts 18 are adjacent the open end of the conduit 4. The arm 19 ispreferably flexible. When water strikes the contacts 18, the water formsa conductive bridge therebetween, thereby completing a circuit.

The gas removal device 9 is configured such that, when the liquiddetection method 17 detects that liquid is flowing through the conduit4, the sucking of gas into the device 9 is ceased, by deactivating thefan 15. This ensures that, during flushing of the toilet 5, liquid isnot sucked into the gas intake port of the gas removal device 9, as thismay block the conduit 13 or cause damage to the fan 15 or motor 16 ofthe gas removal device 9. It is also likely that a circuit board orother control device will be housed within the conduit 13, and clearlythe ingress of water into the conduit 13 is also undesirable if this isthe case.

In circumstance where a user of the toilet (e.g. a child) neglects toflush the toilet following use, the liquid detection mechanism 17 willnot deactivate the gas removal device 9. Hence, in preferred embodimentsof the invention, a timer mechanism T is provided to deactivate the gasremoval device 9 after the elapsing of a predetermined period of timefollowing activation thereof or after the elapsing of a predeterminedperiod of time following determination, by the use detection mechanismUD that use of the toilet 5 has ceased.

The gas removal device 9 further comprises a body portion 20, which isadapted to fit to the exterior shape of the toilet 5. Preferably, thegas removal device 9 is fitted to a toilet such that the interfaceportion 10 and body portion 20 extend directly backwards from theconduit 4 and fit over the back edge of the toilet 5. In order toaccommodate the widest possible variety of different shapes of toilet, avariable length portion 21 is provided to connect the interface portion10 to the body portion 20. The variable length portion 21 may, forexample, comprise a hollow, corrugated, flexible portion, whose lengthmay be varied but still provides an airtight passage between theinterface portion 10 and the body portion 20 of the gas removal device9.

The provision of the variable length portion 21 also assists in ensuringthat the gas removal device 9 may be used within the widest possiblevariety of different toilet systems. If, for example, the configurationof a particular toilet or the presence of other objects in a bathroomprevents the gas removal device 9, from being fitted in theabove-described orientation, the variable length portion 21 willincrease the chances of the gas removal device 9 being able to be fittedin a sideways or other orientation from the conduit 4.

In preferred embodiments of the present invention, the connector 14 thatconnects the conduit 13 to the soil stack 8 comprises a one-way valve V,which allows gas to pass from the conduit 13 into the soil stack 8 butwhich prevents the passage of gas from the soil stack 8 into the conduit13. Advantageously, this one-way valve comprises a flexible diaphragm D,which blocks an aperture in the valve 14 when gas attempts to flow fromthe soil stack 8 to the conduit 13, but distorts to allow gas to flowfrom the conduit 13 to the soil stack 8.

The gas removal device 9 may optionally be powered by a mainsconnection, or may be battery powered. In battery powered embodiments,two rechargeable batteries B may be provided, one of which can berecharged while the other is in use.

FIG. 1 depicts an annular float 22, which may be provided within theinner aperture 11 of the gas removal device 9. The float 22 isconfigured so that if the water level in the toilet rises to the toiletrim (for instance, due to a blockage or malfunction), and water entersthe inner aperture 11 from below, the float 22 will float on the surfaceof the rising water and rise into a position where it blocks the gasintake port of the gas removal device 9. Hence, in the event of the gasremoval device 9 being flooded with water from below, the float 22 willprevent the water entering the gas intake port.

In advantageous embodiments of the invention, one or more turbines orother power generation elements TG are placed in the flow path of aninflow connection WS to the water tank 2 from a mains water supply. Inthese embodiments, the arrangement is such that the flow of water intothe water tank 2 from the mains water supply causes the power generationelements to generate power, which is then supplied to the gas removaldevice 9 or to a battery B thereof.

FIG. 2 shows a perspective view of the interface portion 10 and bodyportion 20 of the gas removal device 9.

It will be understood that the present invention provides a system forremoval of malodorous gases from a toilet which is flexible, effectiveand simple to install.

In the present specification “comprises” means “includes or consists of”and “comprising” means “including or consisting of”.

The features disclosed in the foregoing description, or the followingclaims, or the accompanying drawings, expressed in their specific formsor in terms of a means for performing the disclosed function, or amethod or process for attaining the disclosed result, as appropriate,may, separately, or in any combination of such features, be utilised forrealising the invention in diverse forms thereof.

1. A toilet system comprising: a cistern for containing flush water; atoilet having a bowl, the bowl having one or more apertures which are influid communication with a water intake aperture of the toilet andthrough which flush water flows when the toilet is flushed; a conduitfor transporting flush water from the cistern to the water intakeaperture; and a gas removal device positioned around the conduit anddefining an inner aperture through which the conduit passes, there beinga peripheral space between the exterior of the conduit and an innersurface of the inner aperture, the gas removal device being operable tosuck gas into the device through the inner surface of the inner apertureand comprising a liquid detection mechanism to detect the flow of liquidthrough the conduit and cease the sucking of gas into the device uponsuch detection.
 2. A system according to claim 1, wherein the gasremoval device comprises an interface portion which is positioned aroundthe conduit, the interface portion being provided with a pair of sealsto seal the interface portion to the toilet and to the water tank.
 3. Asystem according to claim 1, wherein the liquid detection mechanismcomprises a pair of electrically conductive contacts, having a gapdefined therebetween, mounted on an arm such that the contacts are in aflow path of liquid carried by the conduit, an electrical connectionbetween the contacts being made by the presence of water in the gapbetween the contacts.
 4. A system according to claim 1, whereinfollowing the ceasing of sucking of gas into the gas removal device dueto the detection of a flow of liquid through the conduit, the sucking ofgas into the gas removal device is resumed once no more liquid isdetected flowing through the conduit.
 5. A system according to claim 1,further comprising a use detection mechanism to detect use of the toiletand activate the gas removal device in response to such detection.
 6. Asystem according to claim 5, wherein the use detection mechanismcomprises a pressure sensor operable to detect the weight of a personusing the toilet.
 7. A system according to claim 5, wherein the usedetection mechanism comprises a wireless connection to the gas removaldevice.
 8. A system according to claim 5, further comprising a timermechanism operable to deactivate the gas removal device after apredetermined time has elapsed following a time when the detectionmechanism detects that use of the toilet has ceased.
 9. A systemaccording to claim 1, further comprising a conduit for guiding gasremoved by the gas removal device and feeding the removed gas into asoil stack of the toilet system.
 10. A system according to claim 9,further comprising a one-way valve which allows the removed gas to befed into the soil stack from the conduit but prevents gas from enteringthe conduit from the soil stack.
 11. A system according to claim 10,wherein the one-way valve comprises a flexible diaphragm which blocks anaperture in the valve when gas attempts to flow from the soil stack tothe conduit but distorts to allow gas to flow from the conduit to thesoil stack.
 12. A system according to claim 1, wherein an internaldiameter of the inner aperture is at least 6.3 cm.
 13. A systemaccording to claim 1, wherein the gas removal device comprises one ormore batteries to provide power to the gas removal device.
 14. A systemaccording to claim 13, wherein the one or more batteries arerechargeable.
 15. A system according to claim 1, further comprising oneor more turbines adapted to be located in an area of the toiletexperiencing, in use, a fluid flow, the flow of fluid past the one ormore turbines producing power, and a connector to supply power soproduced to the gas removal device or a battery thereof.
 16. A systemaccording to claim 1, wherein the gas removal device comprises a bodythat is adapted to fit closely to a portion of the toilet, a part of thebody having variable length.
 17. A system according to claim 16, whereinthe part of the body having a variable length comprises a hollow,corrugated, flexible portion.
 18. A toilet system comprising: a toilethaving a bowl, the bowl having one or more apertures which are in fluidcommunication with a water intake aperture of the toilet and throughwhich flush water flows when the toilet is flushed; a cistern forcontaining flush water, the cistern having an outlet through which flushwater is ejected when the toilet is flushed, the cistern and the toiletbeing arranged such that, when flush water is ejected from the cisternthrough the outlet thereof, a flow of flush water follows a flow pathand is received through the water intake aperture of the toilet; and agas removal device having an inner aperture, the gas removal devicebeing positioned around the flow path such that the flow path passesthrough the inner aperture and, when water flows along the flow path, anair gap exists between an inner surface of the inner aperture and anexterior of the flow, the gas removal device being operable to suck gasinto the device through the inner surface of the cistern outlet, andcomprising a liquid detection mechanism to detect the flow of liquidthrough the inner aperture and cease the sucking of gas into the deviceupon such detection.
 19. A system according to claim 18, wherein thediameter of the inner aperture is at least 6.3 cm.
 20. A gas removaldevice for use with a toilet system comprising a toilet having a bowl,the bowl having one or more apertures which are in fluid communicationwith a water intake aperture of the toilet and through which flush waterflows when the toilet is flushed and a cistern for containing flushwater, the cistern having an outlet through which flush water is ejectedwhen the toilet is flushed, the cistern and the toilet being arrangedsuch that, when flush water is ejected from the cistern through theoutlet thereof, a flow of flush water follows a flow path and isreceived through the water intake aperture of the toilet, the gasremoval device: defining an inner aperture; being adapted to bepositioned around the flow path such that the flow path passes throughthe inner aperture and, when flush water flows through the flow path, anair gap exists between an inner surface of the inner aperture and anexterior of the flow; being operable to suck gas into the device throughan inner surface of the inner aperture; and comprising a liquiddetection mechanism to detect the flow of liquid through the cisternoutlet and cease the sucking of gas into the device upon such detection.21. A device according to claim 20, wherein an internal diameter of theinner aperture is at least 6.3 cm.
 22. A device according to claim 20,wherein the liquid detection mechanism comprises a pair of electricallyconductive contacts, having a gap defined therebetween, mounted on anarm, an electrical connection between the contacts being made by thepresence of water in the gap between the contacts.
 23. A deviceaccording to claim 20, further comprising a use detection mechanism todetect use of the toilet and activate the gas removal device in responseto such detection.
 24. A device according to claim 23, wherein the usedetection mechanism comprises a pressure sensor operable to detect theweight of a person using the toilet.
 25. A device according to claim 23,wherein the use detection mechanism comprises a wireless connection tothe gas removal device.
 26. A device according to claim 23, furthercomprising a timer mechanism operable to deactivate the gas removaldevice after a predetermined time has elapsed following a time when thedetection mechanism detects that use of the toilet has ceased, or aftera predetermined time has elapsed following the initial activation of thegas removal device.
 27. A device according to claim 20, furthercomprising a conduit for guiding gas removed by the gas removal deviceand adapted to feed the removed gas into a soil stack of the toilet. 28.A device according to claim 27, further comprising a one-way valve whichallows the removed gas to be fed into the soil stack from the conduitbut prevents gas from entering the conduit from the soil stack.
 29. Adevice according to claim 28, wherein the one-way valve comprises aflexible diaphragm which blocks an aperture in the valve when gasattempts to flow from the soil stack to the conduit but distorts toallow gas to flow from the conduit to the soil stack.
 30. A deviceaccording to claim 20, wherein the gas removal device comprises one ormore batteries to provide power to the gas removal device.
 31. A deviceaccording to claim 30, wherein the one or more batteries arerechargeable.
 32. A device according to claim 20, further comprising:one or more turbines adapted to be located in an area of the toiletexperiencing, in use, a fluid flow, the flow of fluid past the one ormore turbines producing power; and a connector to supply power soproduced to the gas removal device or a battery thereof.
 33. A deviceaccording to claim 20, wherein the gas removal device comprises a bodythat is adapted to fit closely to a portion of the toilet, a part of thebody having variable length.
 34. A device according to claim 33, whereinthe part of the body having a variable length comprises a hollow,corrugated, flexible portion.
 35. A method of adapting a toilet system,the toilet system initially comprising a toilet having a bowl, the bowlhaving one or more apertures which are in fluid communication with awater intake aperture of the toilet and through which flush water flowswhen the toilet is flushed and a cistern for containing flush water, thecistern having an outlet through which flush water is ejected when thetoilet is flushed, the cistern and the toilet being arranged such that,when flush water is ejected from the cistern through the outlet thereof,a flow of flush water follows a flow path and is received in the waterintake aperture of the toilet, the method comprising the steps of:providing a gas removal device, the gas removal device defining an inneraperture, being operable to suck gas into the device through an innersurface of the inner aperture, and comprising a liquid detectionmechanism to detect the flow of liquid through the cistern outlet andcease the sucking of gas into the device upon such detection; andpositioning the gas removal device around the flow path such that, whenflush water flows along the flow path, an air gap exists between theinner surface of the inner aperture and an exterior of the flow.